This has been discussed ad nauseum. All the gas in a region usually comes from the same refiner. The differences lie in quality control and the additives that each brand provides.

Go with a brand-name for peace of mind, but do realize that it actually makes no difference where you go. It's also not a bad idea to change the brand every few weeks or so, in order to ensure that you are constantly getting a different mix of additives - which reduce deposits.